Effect of azithromycin in combination with simvastatin in the treatment of chronic obstructive pulmonary disease complicated by pulmonary arterial hypertension

Effect of high-flow nasal oxygen therapy combined with ipratropium bromide on Th1/Th2 balance and inflammation in patients with chronic obstructive pulmonary disease and respiratory failure

Objective

To investigate the effect of a combination of high-flow nasal oxygen therapy (HFNO) and ipratropium bromide (IB) on Th1/Th2 balance and inflammation in patients with chronic obstructive pulmonary disease (COPD) and respiratory failure (RF).

Methods

A retrospective analysis was conducted on the clinical data of patients with COPD and RF admitted to the Affiliated Nanjing Brain Hospital of Nanjing Medical University from June 2021 to March 2023. A total of 162 patients were included, with 79 patients received respiratory support using HFNO (HFNO group) and 83 patients who were treated using combined HFNO/IB (combined group). Treatment effect, lung function, levels of Th1/Th2, and inflammatory state were compared before and after the treatment.

Results

Total effeicacy of patients in the combined group was significantly higher than that of the HFNO group (P<0.05). After the treatment, pulmonary function levels of the two groups was higher than that before the treatment, and was significantly better in the combined group compared to the HFNO group (P<0.05). The treatment was associated with a significant increase in the levels of Th1/Th2 in both groups. Post-treatment levels of these indexes in the combined group were markedly higher compared to the HFNO group (P<0.05). After the treatment, the inflammatory response of the two groups decreased, and was lower in the combined group that in the HFNO group (P<0.05).

Conclusions

In COPD patients with RF, HFNO combined with IB is efficient in alleviating the inflammatory state of patients, restoring Th1/Th2 balance, and improving lung function compared to HFNO alone.

A Double-Blind, Randomized, Placebo-controlled Trial of Long-Term Doxycycline Therapy on Exacerbation Rate in Patients with Stable Chronic Obstructive Pulmonary Disease

Rationale: Chronic obstructive pulmonary disease (COPD) exacerbations are a major cause of morbidity and mortality, and preventing them is a key treatment target. Long-term macrolide treatment is effective at reducing exacerbations, but there is a paucity of evidence for other antibiotic classes. Objectives: To assess whether 12-month use of doxycycline reduces the exacerbation rate in people with COPD. Methods: People with moderate to very severe COPD and an exacerbation history were recruited from three UK centers and randomized to 12 months of doxycycline 100 mg once daily or placebo. The primary study outcome was the exacerbation rate per person-year. Results: A total of 222 people were randomized. Baseline mean FEV1 was 1.35 L (SD, 0.35 L), 52.5% predicted (SD, 15.9% predicted). The median number of treated exacerbations in the year before the study was 2 (SD, 1-4). A total of 71% of patients reported two or more exacerbations, and 81% were already prescribed inhaled corticosteroids at baseline. The COPD exacerbation rate did not differ between the groups (doxycycline/placebo rate ratio [RR], 0.86; 95% confidence interval [CI], 0.67-1.10; P = 0.23). No difference was seen if only treated exacerbations or hospitalizations were considered. In preplanned subgroup analysis, doxycycline appeared to better reduce the exacerbation rate among people with severe COPD (RR, 0.36; 95% CI, 0.15-0.85; P = 0.019) and in those with an eosinophil count <300 cells/μl (RR, 0.50; 95% CI, 0.29-0.84; P = 0.01). Health status measured by St. George's Respiratory Questionnaire was 5.2 points worse in the doxycycline group at 12 months (P < 0.007). Conclusions: Doxycycline did not significantly reduce the exacerbation rate, over 12 months, in participants with COPD who exacerbated regularly, but it may have benefitted those with more severe COPD or blood eosinophil counts <300 cells/μl. Clinical trial registered with www.clinicaltrials.gov (NCT02305940).

Clinical study on the effect of Bi-level positive airway pressure therapy on COPD complicated with Anxiety and Depression

Objectives

To investigate the effect of bi-level positive airway pressure (BIPAP) therapy on chronic obstructive pulmonary disease (COPD) complicated with anxiety and depression.

Methods

This is a retrospective study. One hundred patients with COPD complicated with anxiety and depression who were admitted to the Respiratory Department of The First Affiliated Hospital of Hebei North University from August 2021 to August 2022 were selected and randomly divided into two groups. Patients in the control group were given conventional symptomatic treatment, while those in the observation group were given BIPAP therapy in addition to the treatment in the control group. The two groups were compared and analyzed in terms of respiratory function indicators, the changes in the scores of St. George's Hospital Respiratory Questionnaire (SGRQ) and COPD assessment test (CAT), blood gas analysis indicators, the levels of serum neurokinin A (NKA), serum interleukin-6 (IL-6), and serum serotonin (5-HT), as well as the changes in the scores of Hamilton Anxiety Scale (HAMA) and Hamilton Depression Scale (HAMD).

Results

After treatment, the levels of lung function indicators in both groups increased, SGRQ and CAT scores decreased, and pH levels remained unchanged. In addition, PaO2 levels increased, PCO2, 5-HT, NKA and IL-6 levels decreased, and HAMA and HAMD scores decreased. The improvement degree of each indicator in the observation group was superior to that in the control group.

Conclusion

In the clinical treatment of COPD complicated with anxiety and depression, BIPAP boasts effective amelioration of lung function and relief of anxiety and depression symptoms, and its mechanism of action may have a close bearing on ameliorating the levels of 5-HT, NKA, and IL-6 in patients.

A narrative review of research advances in hypoxic pulmonary hypertension

Background and Objective

Hypoxic pulmonary hypertension (HPH) is a pathological syndrome characterized by pulmonary vasoconstriction and pulmonary vascular remodeling caused by hypoxia, which eventually leads to right heart failure or death. There are 2 stages of onset of HPH: hypoxic pulmonary vasoconstriction (HPV) and hypoxic pulmonary vascular remodeling (HPVR). It is an important pathophysiological link in the pathogenesis of chronic obstructive pulmonary disease (COPD) and chronic mountain sickness (CMS), and its severity is closely related to the course and prognosis of COPD and CMS. However, there is a lack of systematic review on the diagnosis, pathogenesis and treatment of HPH. The objective of this paper is to review the diagnosis, pathogenesis, treatment of HPH.

Methods

In this paper, the method of literature review is adopted to obtain the information about HPH. Based on the literature, comprehensive and systematic review is made. The diagnosis, pathogenesis, treatment of HPH are summarized.

Key Content and Findings

Right heart catheterization is the gold standard for diagnosing HPH. Hypoxia-inducible factor, oxidative stress, metal metabolism, ion channel, inflammatory cytokines, cell apoptosis and vascular factors are the main pathogenesis of HPH. The treatment of HPH includes long-term oxygen therapy, statins, prostaglandins, phosphodiesterase inhibitor and ET receptor antagonists.

Conclusions

Although great progress has been made in the pathophysiology and molecular biology of HPH, it is still unclear which factors play a leading role in the pathogenesis of HPH, and no breakthrough has been made in the treatment of HPH. It is believed that the specific mechanism will be revealed as the research continues, and earlier diagnosis and the development of more effective targeted drugs will be the focus of future research.

Treatment of pulmonary hypertension associated with COPD: a systematic review

Chronic obstructive pulmonary disease-associated pulmonary hypertension (COPD-PH) is an increasingly recognised condition which contributes to worsening dyspnoea and poor survival in COPD. It is uncertain whether specific treatment of COPD-PH, including use of medications approved for pulmonary arterial hypertension (PAH), improves clinical outcomes. This systematic review and meta-analysis assesses potential benefits and risks of therapeutic options for COPD-PH.

We searched Medline and Embase for relevant publications until September 2020. Articles were screened for studies on treatment of COPD-PH for at least 4 weeks in 10 or more patients. Screening, data extraction, and risk of bias assessment were performed independently in duplicate. When possible, relevant results were pooled using the random effects model.

Supplemental long-term oxygen therapy (LTOT) mildly reduced mean pulmonary artery pressure (PAP), slowed progression of PH, and reduced mortality, but other clinical or functional benefits were not assessed. Phosphodiesterase type 5 inhibitors significantly improved systolic PAP (pooled treatment effect −5.9 mmHg; 95% CI −10.3, −1.6), but had inconsistent clinical benefits. Calcium channel blockers and endothelin receptor antagonists had limited haemodynamic, clinical, or survival benefits. Statins had limited clinical benefits despite significantly lowering systolic PAP (pooled treatment effect −4.6 mmHg; 95% CI −6.3, −2.9).

This review supports guideline recommendations for LTOT in hypoxaemic COPD-PH patients as well as recommendations against treatment with PAH-targeted medications. Effective treatment of COPD-PH depends upon research into the pathobiology and future high-quality studies comprehensively assessing clinically relevant outcomes are needed.

The presence of PH in COPD patients is associated with worsening morbidity and mortality. These findings support guideline recommendations for LTOT in hypoxaemic COPD-PH patients as well as recommendations against treatment using PAH-targeted medications.https://bit.ly/3Al4rLb

Bosentan combined with sildenafil in the treatment of COPD patients with pulmonary arterial hypertension

OBJECTIVE

To explore the impacts of bosentan combined with sildenafil on chronic obstructive pulmonary disease (COPD) patients with pulmonary arterial hypertension (PAH).

METHODS

From April 2019 to October 2020, 90 COPD patients with PAH diagnosed in our hospital were recruited and divided into groups A and B. The patients in group A (50 cases) were treated with bosentan combined with sildenafil, and the patients in group B (40 cases) were administered bosentan combined with iloprost solution for inhalation. The PAH conditions, the heart rates (HR), the cardiac function, the pulmonary function, the blood gas indexes, the inflammatory factor expressions, the incidences of adverse reactions, the overall response rates (ORR), and the patient satisfaction levels were determined or evaluated.

RESULTS

Compared with group B, the patients in group A had better recovered PAH, HR, cardiac function, pulmonary function, and blood gas indexes, lower inflammatory factor expression levels and a lower incidence of adverse reactions, as well as higher ORR and higher satisfaction levels.

CONCLUSION

Bosentan combined with sildenafil can reduce pulmonary artery pressure and promote the recovery of cardiopulmonary function in COPD patients with PAH.

Prophylactic antibiotics for adults with chronic obstructive pulmonary disease: a network meta-analysis

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a chronic respiratory condition characterised by persistent respiratory symptoms and airflow limitation. Acute exacerbations punctuate the natural history of COPD and are associated with increased morbidity and mortality and disease progression. Chronic airflow limitation is caused by a combination of small airways (bronchitis) and parenchymal destruction (emphysema), which can impact day-to-day activities and overall quality of life. In carefully selected patients with COPD, long-term, prophylactic use of antibiotics may reduce bacterial load, inflammation of the airways, and the frequency of exacerbations.

OBJECTIVES

To assess effects of different prophylactic antibiotics on exacerbations, quality of life, and serious adverse events in people with COPD in three separate network meta-analyses (NMAs), and to provide rankings of identified antibiotics.

SEARCH METHODS

To identify eligible randomised controlled trials (RCTs), we searched the Cochrane Airways Group Specialised Register of trials and clinical trials registries. We conducted the most recent search on 22 January 2020.

SELECTION CRITERIA

We included RCTs with a parallel design of at least 12 weeks' duration evaluating long-term administration of antibiotics prophylactically compared with other antibiotics, or placebo, for patients with COPD.

DATA COLLECTION AND ANALYSIS

This Cochrane Review collected and updated pair-wise data from two previous Cochrane Reviews. Searches were updated and additional studies included. We conducted three separate network meta-analyses (NMAs) within a Bayesian framework to assess three outcomes: exacerbations, quality of life, and serious adverse events. For quality of life, we collected data from St George's Respiratory Questionnaire (SGRQ). Using previously validated methods, we selected the simplest model that could adequately fit the data for every analysis. We used threshold analysis to indicate which results were robust to potential biases, taking into account each study's contributions to the overall results and network structure. Probability ranking was performed for each antibiotic class for exacerbations, quality of life, and serious adverse events.

MAIN RESULTS

Characteristics of studies and participants Eight trials were conducted at multiple sites that included hospital clinics or academic health centres. Seven were single-centre trials conducted in hospital clinics. Two trials did not report settings. Trials durations ranged from 12 to 52 weeks. Most participants had moderate to severe disease. Mean age ranged from 64 years to 73 years, and more males were recruited (51% to 100%). Forced expiratory volume in one second (FEV₁) ranged from 0.935 to 1.36 L. Most participants had previous exacerbations. Data from 12 studies were included in the NMAs (3405 participants; 16 treatment arms including placebo). Prophylactic antibiotics evaluated were macrolides (azithromycin and erythromycin), tetracyclines (doxycyclines), quinolones (moxifloxacin) and macrolides plus tetracyclines (roxithromycin plus doxycycline). Risk of bias and threshold analysis Most studies were at low risk across domains, except detection bias, for which only seven studies were judged at low risk. In the threshold analysis for exacerbations, all comparisons in which one antibiotic was compared with another were robust to sampling variation, especially macrolide comparisons. Comparisons of classes with placebo were sensitive to potential bias, especially macrolide versus placebo, therefore, any bias in the comparison was likely to favour the active class, so any adjustment would bring the estimated relative effect closer to the null value, thus quinolone may become the best class to prevent exacerbations. Exacerbations Nine studies were included (2732 participants) in this NMA (exacerbations analysed as time to first exacerbation or people with one or more exacerbations). Macrolides and quinolones reduced exacerbations. Macrolides had a greater effect in reducing exacerbations compared with placebo (macrolides: hazard ratio (HR) 0.67, 95% credible interval (CrI) 0.60 to 0.75; quinolones: HR 0.89, 95% CrI 0.75 to 1.04), resulting in 127 fewer people per 1000 experiencing exacerbations on macrolides. The difference in exacerbations between tetracyclines and placebo was uncertain (HR 1.29, 95% CrI 0.66 to 2.41). Macrolides ranked first (95% CrI first to second), with quinolones ranked second (95% CrI second to third). Tetracyclines ranked fourth, which was lower than placebo (ranked third). Contributing studies were considered as low risk of bias in a threshold analysis. Quality of life (SGRQ) Seven studies were included (2237 participants) in this NMA. SGRQ scores improved with macrolide treatment compared with placebo (fixed effect-fixed class effect: mean difference (MD) -2.30, 95% CrI -3.61 to -0.99), but the mean difference did not reach the minimally clinical important difference (MCID) of 4 points. Tetracyclines and quinolones did not improve quality of life any more than placebo, and we did not detect a difference between antibiotic classes. Serious adverse events Nine studies were included (3180 participants) in the NMA. Macrolides reduced the odds of a serious adverse event compared with placebo (fixed effect-fixed class effect: odds ratio (OR) 0.76, 95% CrI 0.62 to 0.93). There was probably little to no difference in the effect of quinolone compared with placebo or tetracycline plus macrolide compared with placebo. There was probably little to no difference in serious adverse events between quinolones or tetracycline plus macrolide. With macrolide treatment 49 fewer people per 1000 experienced a serious adverse event compared with those given placebo. Macrolides ranked first, followed by quinolones. Tetracycline did not rank better than placebo. Drug resistance Ten studies reported drug resistance. Results were not combined due to variation in outcome measures. All studies concluded that prophylactic antibiotic administration was associated with the development of antimicrobial resistance.

AUTHORS' CONCLUSIONS

This NMA evaluated the safety and efficacy of different antibiotics used prophylactically for COPD patients. Compared to placebo, prolonged administration of macrolides (ranked first) appeared beneficial in prolonging the time to next exacerbation, improving quality of life, and reducing serious adverse events. No clear benefits were associated with use of quinolones or tetracyclines. In addition, antibiotic resistance was a concern and could not be thoroughly assessed in this review. Given the trade-off between effectiveness, safety, and risk of antibiotic resistance, prophylactic administration of antibiotics may be best reserved for selected patients, such as those experiencing frequent exacerbations. However, none of the eligible studies excluded patients with previously isolated non-tuberculous mycobacteria, which would contraindicate prophylactic administration of antibiotics, due to the risk of developing resistant non-tuberculous mycobacteria.

Efficacy and safety of statin therapy in pulmonary hypertension: a systematic review and meta-analysis

Background

Pulmonary hypertension (PH) is a multi-causal disease and no satisfactory therapeutic strategies for it. Statins have been suggested as potential drugs in PH, whose effects in different clinic types of PH have not been conclusive. In this study, we included randomized controlled clinical trials (RCTs) evaluating the efficacy and safety of statins therapy in PH.

Methods

We searched databases including Medline, Embase, Cochrane, PubMed and Web of science, with time up to January 1, 2019. With 95% confidence interval (CI), weighted mean difference (WMD) or standardized mean difference (SMD) was pooled and calculated in a random or fixed effect model according to I2 statistic.

Results

A total of nine RCTs with 657 patients were included. Four types of statins (atorvastatin, pravastatin, rosuvastatin and simvastatin) were used at different doses (10-80 mg daily) for up to 6 months. In the pooled-data analysis, compared with placebo, there were significant improvements in pulmonary arterial pressure (PAP), in addition to low-density lipoprotein (LDL) in patients treated with statins, but not in 6-minute walking distance (6MWD), cardiac index (CDI). No more adverse events and all-cause mortality were revealed. Subgroup analysis indicated that statins could decrease PAP in the subtype of PH due to chronic obstructive pulmonary disease (COPD), but not pulmonary arterial hypertension (PAH).

Conclusions

This study indicates that statins can efficiently and safely reduce PAP in PH, especially in the subtype due to COPD. Further RCTs are needed to focus on the efficacy and safety of statin therapy in different subtypes of PH.

Effects of long-term macrolide therapy at low doses in stable COPD

Background: Chronic obstructive pulmonary disease (COPD) is currently the fourth largest fatal disease in the world, and is expected to rise to third place by 2020. Frequent acute exacerbations lead to increased mortality. Some suggestions for prophylactic use of macrolides in preventing COPD exacerbations have been raised, but there are still several issues that need to be addressed, such as target population, the course of treatment, therapeutic dose, and so on.

Objective: To evaluate, via exploratory meta-analysis, the efficacy of long-term macrolide therapy at low doses in stable COPD.

Methods: A systematic literature search was performed in PubMed, Embase, and Cochrane database from inception to March 28, 2019. Randomized controlled trials (RCT) which reported long-term use of macrolides in prevention of COPD were eligible.

Results: A total of 10 articles were included in this study. It was found that there was a 23% relative risk reduction in COPD exacerbations among patients taking macrolides compared to placebo (P<0.01). The median time to first exacerbation was effectively prolonged among patients taking macrolides vs placebo (P<0.01). Sub-group analysis showed erythromycin was advantageous and older patients were less responsive to macrolides.

Conclusions: Long-term low dose usage of macrolides could significantly reduce the frequency of the acute exacerbation of COPD. The treatment was well tolerated, with few adverse reactions, but it was not suitable for the elderly. It is recommended that this treatment regimen could be used in patients with GOLD grading C or D, because they have a higher risk of acute exacerbation and mortality. It needs to be further discussed whether this treatment should last for 12 months or longer.

Secondary pulmonary arterial hypertension: to treat or not to treat?

PURPOSE OF REVIEW

The purpose of this review is to review recent literature related to mechanisms and treatment options for 'secondary' (i.e., WHO Groups 3 and 5) pulmonary arterial hypertension (PAH).

RECENT FINDINGS

Published randomized controlled trials, in general, do not support the use of approved therapies for 'primary' (i.e., WHO Group 1) PAH patients in patients with Group 3 PAH because of the small numbers of patients and inconsistent benefit. Therefore, we currently recommend against the use of these medications for Group 3 PAH. Similarly, there is limited evidence supporting the use of Group 1 PAH medications in Group 5 patients. In most patients with Group 5 PAH, treatment should be directed to the underlying disease.

SUMMARY

The utility of PAH-specific therapy in WHO Group 3 PAH is unclear because of the small numbers of patients evaluated and inconsistent beneficial effects observed. There is limited evidence supporting the use of PAH medications in Group 5 patients, and they may be harmful in some cases.

Prophylactic antibiotic therapy for chronic obstructive pulmonary disease (COPD)

BACKGROUND

There has been renewal of interest in the use of prophylactic antibiotics to reduce the frequency of exacerbations and improve quality of life in chronic obstructive pulmonary disease (COPD).

OBJECTIVES

To determine whether or not regular (continuous, intermittent or pulsed) treatment of COPD patients with prophylactic antibiotics reduces exacerbations or affects quality of life.

SEARCH METHODS

We searched the Cochrane Airways Group Trials Register and bibliographies of relevant studies. The latest literature search was performed on 27 July 2018.

SELECTION CRITERIA

Randomised controlled trials (RCTs) that compared prophylactic antibiotics with placebo in patients with COPD.

DATA COLLECTION AND ANALYSIS

We used the standard Cochrane methods. Two independent review authors selected studies for inclusion, extracted data, and assessed risk of bias. We resolved discrepancies by involving a third review author.

MAIN RESULTS

We included 14 studies involving 3932 participants in this review. We identified two further studies meeting inclusion criteria but both were terminated early without providing results. All studies were published between 2001 and 2015. Nine studies were of continuous macrolide antibiotics, two studies were of intermittent antibiotic prophylaxis (three times per week) and two were of pulsed antibiotic regimens (e.g. five days every eight weeks). The final study included one continuous, one intermittent and one pulsed arm. The antibiotics investigated were azithromycin, erythromycin, clarithromycin, doxycyline, roxithromycin and moxifloxacin. The study duration varied from three months to 36 months and all used intention-to-treat analysis. Most of the pooled results were of moderate quality. The risk of bias of the included studies was generally low.The studies recruited participants with a mean age between 65 and 72 years and mostly at least moderate-severity COPD. Five studies only included participants with frequent exacerbations and two studies recruited participants requiring systemic steroids or antibiotics or both, or who were at the end stage of their disease and required oxygen. One study recruited participants with pulmonary hypertension secondary to COPD and a further study was specifically designed to asses whether eradication of Chlamydia pneumoniae reduced exacerbation rates.The co-primary outcomes for this review were the number of exacerbations and quality of life.With use of prophylactic antibiotics, the number of participants experiencing one or more exacerbations was reduced (odds ratio (OR) 0.57, 95% CI 0.42 to 0.78; participants = 2716; studies = 8; moderate-quality evidence). This represented a reduction from 61% of participants in the control group compared to 47% in the treatment group (95% CI 39% to 55%). The number needed to treat for an additional beneficial outcome with prophylactic antibiotics given for three to 12 months to prevent one person from experiencing an exacerbation (NNTB) was 8 (95% CI 5 to 17). The test for subgroup difference suggested that continuous and intermittent antibiotics may be more effective than pulsed antibiotics (P = 0.02, I² = 73.3%).The frequency of exacerbations per patient per year was also reduced with prophylactic antibiotic treatment (rate ratio 0.67; 95% CI 0.54 to 0.83; participants = 1384; studies = 5; moderate-quality evidence). Although we were unable to pool the result, six of the seven studies reporting time to first exacerbation identified an increase (i.e. benefit) with antibiotics, which was reported as statistically significant in four studies.There was a statistically significant improvement in quality of life as measured by the St George's Respiratory Questionnaire (SGRQ) with prophylactic antibiotic treatment, but this was smaller than the four unit improvement that is regarded as being clinically significant (mean difference (MD) -1.94, 95% CI -3.13 to -0.75; participants = 2237; studies = 7, high-quality evidence).Prophylactic antibiotics showed no significant effect on the secondary outcomes of frequency of hospital admissions, change in forced expiratory volume in one second (FEV1), serious adverse events or all-cause mortality (moderate-quality evidence). There was some evidence of benefit in exercise tolerance, but this was driven by a single study of lower methodological quality.The adverse events that were recorded varied among the studies depending on the antibiotics used. Azithromycin was associated with significant hearing loss in the treatment group, which was in many cases reversible or partially reversible. The moxifloxacin pulsed study reported a significantly higher number of adverse events in the treatment arm due to the marked increase in gastrointestinal adverse events (P < 0.001). Some adverse events that led to drug discontinuation, such as development of long QTc or tinnitus, were not significantly more frequent in the treatment group than the placebo group but pose important considerations in clinical practice.The development of antibiotic resistance in the community is of major concern. Six studies reported on this, but we were unable to combine results. One study found newly colonised participants to have higher rates of antibiotic resistance. Participants colonised with moxifloxacin-sensitive pseudomonas at initiation of therapy rapidly became resistant with the quinolone treatment. A further study with three active treatment arms found an increase in the degree of antibiotic resistance of isolates in all three arms after 13 weeks treatment.

AUTHORS' CONCLUSIONS

Use of continuous and intermittent prophylactic antibiotics results in a clinically significant benefit in reducing exacerbations in COPD patients. All studies of continuous and intermittent antibiotics used macrolides, hence the noted benefit applies only to the use of macrolide antibiotics prescribed at least three times per week. The impact of pulsed antibiotics remains uncertain and requires further research.The studies in this review included mostly participants who were frequent exacerbators with at least moderate-severity COPD. There were also older individuals with a mean age over 65 years. The results of these studies apply only to the group of participants who were studied in these studies and may not be generalisable to other groups.Because of concerns about antibiotic resistance and specific adverse effects, consideration of prophylactic antibiotic use should be mindful of the balance between benefits to individual patients and the potential harms to society created by antibiotic overuse. Monitoring of significant side effects including hearing loss, tinnitus, and long QTc in the community in this elderly patient group may require extra health resources.